Chirico and Ypsilon fire as they circle around each other. Ypsilon closes in and knocks Chirico to the ground. Two Fattys attack from nearby, but Ypsilon destroys them. Chirico takes advantage of the distraction and breaks away from Ypsilon. The two continue to shoot at each other and in the process ignite nearby stores of ammunition. As the entire area explodes, Rochina and Fyana retreat. A massive explosion damages both ATs and sends them falling into a deep underground tunnel. Outside, the Balarant Leslion ship takes off to escape the explosion. Deep underground, Ypsilon approaches Chirico’s immobilized Fatty. Chirico aims his gun at the Strike Dog and opens his cockpit. Ypsilon tells Chirico to kill him, and Chirico asks Ypsilon what he would do if their positions were reversed. Ypsilon says he would kill Chirico without hesitation, and Chirico wonders if he really would. As the dust clears, Gotho, Coconna and Vanilla look at the pile of rubble and wonder if Chirico will be safe. Rochina orders his men to begin digging through the rubble to find Chirico and Ypsilon. Ypsilon tells Chirico to kill him any time he wants, and he asks Chirico if he’s hesitating because his opponent is unarmed. Chirico jumps out of the cockpit and says that now their positions are reversed. Ypsilon pulls his gun out and asks Chirico what he’s trying to do. Chirico says that both their ATs are damaged, and it’s easier for two men to dig through the rubble than one. He tells Ypsilon he can decide whether to help him or kill him. On the Balarant ship, Fyana worries about Chirico and asks Rochina why he set up the battle between Chirico and Ypsilon. Rochina says it’s an experiment because he wants to know how Chirico can equal a PS in battle. He’s sure that Chirico will survive, and Fyana suspects he knows something about Chirico. Chirico digs through the rubble while held at gunpoint by Ypsilon. He tells Ypsilon to hurry up and decide whether to kill him or help him. Ypsilon asks Chirico why he won’t kill him, and Chirico thinks it’s because they’re alike. Ypsilon refutes that claim and says only Proto One is like him. He asks Chirico why he calls her Fyana, and even Chirico himself isn’t sure. Reluctantly, Ypsilon decides to help Chirico out of personal pride.
The Fattys continue to dig through the rubble, and through the use of sensor equipment they find two life signs. Rochina tells everyone that Chirico is alive, and Gotho thinks he must be immortal. In space, the scout ship reports to Futtor that Ypsilon is alive and trapped underground. He orders an AT rescue team to go down to Sunsa and get Ypsilon before the Balarant do. The Schmitel twins are eager to analyze Ypsilon and see how he fared in battle against Chirico. Chirico offers his hand to help pull Ypsilon up to a higher ledge, but Ypsilon refuses. Chirico sees that Ypsilon’s oxygen is low, and he thinks they should wait until they are rescued. Ypsilon asks Chirico if he’s afraid of dying, and Chirico says he wants to live. Ypsilon asks if it’s for Fyana’s sake and says he hates both of them. He says that as Perfect Soldiers they were the only ones of their kind and were meant to have a glorious future of battle. Chirico says there’s no glory in battle, and Ypsilon calls him a mere human. Chirico tells Ypsilon that he’s not special, that he’s just a modified human honed to be nothing more than a weapon. He then says that Ypsilon should stop getting so excited because it uses up air. Ypsilon sits down and says that they only way they’re alike is that their combat skills are equal. The Fattys dig through the rubble and create an opening above Chirico and Ypsilon. Before they part ways, Ypsilon tells Chirico that he’ll be back for their final duel. Ypsilon runs off and is met by two Standing Tortoise pilots who brought a spare unit for him. The Fattys spot Ypsilon and attack, but he destroys them and escapes in an AT Landing Craft. Rochina asks Chirico when he will have his rematch, and Chirico says he’ll tell him when the time is right. Rochina keeps his part of the bargain and sends Vanilla, Coconna and Gotho away in a small ship. Fyana asks Chirico to stop the fighting because there’ll never be an end to it. Chirico tells her it’ll end when one of them is dead.
Chirico and Ypsilon’s duel is interrupted by the unfortunate fact that they were fighting in an ammo dump and set off a huge explosion. Being trapped together gives them their first chance to speak outside of battle. Ypsilon is deluded by ideas of a glorious destiny in battle. However, because of his experiences, he has gone from loving Fyana to hating her. He still believes he’s a superior form of human to Chirico, but at least he admits that Chirico can fight as well as a PS. He denies that they’re alike, but they in fact have a lot in common. Both are manipulated to fight by forces at work in the background for secret purposes. Both are in love with Fyana and are willing to die for her. The question remains though, how exactly does Chirico fight so well against Perfect Soldiers?